TUFLOW Message 3201

TUFLOW Message
ERROR 3201: Error in U face proxy: face <id>, proxy face = <id>, proxy cells <id> and <id> not within the same sub-subdomain

Alternate Message
NA

Message Type
ERROR

Description
Quadtree BC Parallel Inertia Approach == Method B extracts velocities from faces parallel to the model boundary (“QT”, “HT” and “HX” types) to calculate the transverse momentum, or parallel inertia at the boundary. For example, to calculate the parallel inertia at the face highlighted by orange circle in the image below, the transverse velocity from the non-BC-face below is needed. However, if the boundary cells are distributed across multiple CPU or GPU devices (illustrated by the red dot line), it can require velocity information from a face within another device. This could cause memory access violation during the simulation, thus the ERROR message is generated to stop the simulation.

Suggestions
Revise quadtree refinement polygon to ensure the cell size does not change immediately inside the model boundary. The image below shows a good example, where 2 rows of cells have the same size and this ensures the face the boundary faces selected by the Quadtree BC Parallel Inertia Approach == Method B are always within the same CPU/GPU device.

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